The allegation follows an investigation into the Bombers launched by ASADA and the AFL in February, revealing concerns over supplements supplied to their players in 2012.

Anyone who thinks that they can run the gauntlet with the measures that we've put in place ... there's no place for them in our game.

AFL chief executive Andrew Demetriou

While Demetriou insists the AFL will not take action against Hird simply "on the basis of newspaper reports", he says any AFL players using banned substances will be caught.

"Everyone knows that the AFL has taken this matter seriously," he said.

"We've responded immediately to the ACCC report, we've put in some significant and enhanced measures that were approved by the AFL Commission.

"I've also said that anyone who thinks that they can run the gauntlet with the measures that we've put in place, and partake in any activity that's not in keeping with the spirit of the code, that is not in keeping with what is legally acceptable in our code, there's no place for them in our game."

Demetriou says he is shocked by the continuing allegations emerging from ASADA's investigation.

"Of course I'm shocked. I'm shocked by the complexity of the substances, the potential injurous nature of these substances," he said.

"I'm horrified as a parent about the thought - if it's true - that young men were being injected with these substances. It's a terribly disturbing situation."

'Stressful period'

Demetriou says he can understand it will be a stressful period for Hird to be at the centre of a doping allegation.

"James Hird is one of the finest players who ever played the game," he continued.

"He's one of the finest contributors to the Essendon Football Club in its very long and proud history.

"I'm sure that he - at the moment - is feeling very, very disturbed by these allegation, as he's indicated in his statement.

"He, like any individual, is entitled to have his say and to put his case forward and we should, as a minimum afford him that respect.

"So we're looking forward to hearing what he has to say to the ASADA investigators, which will be conveyed back to the AFL as part of the investigation."

Bombers wait

Earlier, Bombers chairman David Evans refused to comment specifically on the allegation made against Hird.

Evans said the Bombers owed it to Hird to wait until he is interviewed by ASADA.

"They (allegations) are of course very serious, but I want to urge caution here," Evans said.

"The board will not be making a decision about these allegations today and it is extremely important James and the others be afforded the opportunity to talk to ASADA and the basic right to natural justice.

"James Hird is a person of great respect at this club and indeed the football community, and the the football community and the the board will not be making decisions about the next steps until the processes of the review and the investigation take their course."

Evans says the Bombers will wait until the ASADA and AFL investigation is completed before taking any action against club figures if required.

He also declined to comment on whether Hird would be stood down from his coaching duties against Fremantle at Subiaco Oval on Friday night, as has been speculated.

"This investigation will take its time and that is taking a toll on our club," Evans continued.

"But I repeat: we must give them the time and space they need to come to the conclusions about what happened and how."